1. Field
The invention relates to an organic electroluminescence display device and a manufacturing method thereof, and more specifically, to an organic electroluminescence display device encapsulated by a frit and a manufacturing method thereof.
2. Discussion of the Related Technology
In general, organic electroluminescence display devices comprise a substrate on which a pixel region and a non-pixel region are provided, and a vessel or another substrate arranged to be opposite to the substrate and attached to the substrate by a sealant such as epoxy for its encapsulation.
On the pixel region of the substrate is formed multiple light-emitting elements connected in a matrix form between a scan line and a data line, the light-emitting elements comprising an anode electrode, a cathode electrode, and an organic thin film layer formed between the anode electrode and cathode electrode. The organic thin film layer generally comprising an hole transport layer, an organic light-emitting layer and an electron transport layer.
The light-emitting elements configured as described above are vulnerable to oxygen exposure because the organic materials are easily oxidized by moisture in the air. In addition, the cathode electrode is generally made of metal materials, subject to oxidation which can cause deterioration to electrical and light-emitting properties. To avoid the above problems, a powder-type moisture absorbent or a film-type moisture absorbent is generally provided on a vessel manufactured in the form of a metal material can or cup, or a substrate made of glass, plastic, etc. to get rid of moisture, oxygen and hydrogen from the exterior.
However, such methods of coating the powder-type moisture absorbent generally involves relatively complicated processes and raises cost for materials and the processes. In addition, such methods result in the increase of the thickness of the display device and is difficult to be applied to an screen light-emitting type display. In addition, such methods of attaching the film-type moisture absorbent have limited capability to eliminate all moisture and also have low durability and reliability. This further limits use of such methods in large scale production. The above discussion is simply to describe the general field of light emitting displays and is not a discussion of the prior art.
Methods have been developed which encapsulate light-emitting elements by forming side walls with frits to overcome the afore-mentioned problems.
International patent application No. PCT/KR2002/000994(May 24, 2002) discloses an encapsuation container formed with side walls using a glass frit and a manufacturing method thereof.
U.S. patent application Ser. No. 10/414,794 (Apr. 16, 2003) discloses a glass package encapsulated by attaching a first and a second glass plates through a frit and a manufacturing method thereof.
Korean patent laying-open gazette No. 2001-0084380(Sep. 6, 2001) discloses a frit frame encapsulation method using a laser.
Korean patent laying-open gazette No. 2002-0051153(Jun. 28, 2002) discloses a packaging method of encapsulating an upper substrate and a lower substrate with a frit layer using a laser.